Chen CPC, Chen MJL, Pei YC, Lew HL, Wong PY, Tang SFT: Sagittal plane loading response during gait in different age groups and in people with knee osteoarthritis. Am J Phys Med Rehabil 2003;82:307–312.
To investigate the gait patterns and the sagittal ground reaction forces in different age groups and in people with knee osteoarthritis.
Motion analysis and force platform data were collected for a total of 55 female subjects capable of independent ambulation. Subjects were divided into three groups consisting of the control group, the elderly group, and the osteoarthritis knee group. Gait parameters of walking velocity, cadence, step length, stride time, single- and double-support time, and sagittal ground reaction forces were obtained during comfortable walking speed. Gait analysis was performed in a tertiary hospital’s gait laboratory. Variables were analyzed using a univariate repeated-measures analysis of variance. Statistical significance was set at a value of P < 0.05.
The osteoarthritis knee group had slower walking velocity, lower cadence, and longer stride time as compared with the elderly and young control groups (P < 0.05). In ground reaction force studies, the first peak time, expressed in percentage of gait cycle, was significantly longer in the osteoarthritis knee group (20.8 ± 3.2) as compared with the elderly (17.8 ± 2.0) and young control groups (17.1 ± 1.8, P < 0.01). The force during time of minimal midstance was larger in the osteoarthritis knee group (90.9 ± 5.3) as compared with the elderly and young control groups (P < 0.05). The second peak force was significantly smaller in the osteoarthritis knee group as compared with the young control group (P < 0.01). The force change in the midfoot region in the osteoarthritis knee and elderly groups revealed more loading force onto the midfoot region during midstance as compared with the young control group (P < 0.01).
Gait parameters in the elderly and osteoarthritis knee patients were characterized by slower walking velocity, lower cadence, shorter step length, longer stride time, and longer double-support time. Less heel contact and push-off forces were noticed in these two groups, with more loading force onto the midfoot during midstance.
From the Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Tao-yuan, Taiwan (CPCC, MJLCC, YCP, PYW, SFTT); and the Comprehensive Rehabilitation Center, Veterans Affairs Palo Alto Health Care System, Stanford University School of Medicine, Palo Alto, California (HLL).
All correspondence and requests for reprints should be addressed to Simon F. T. Tang, MD, Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, 5, Fu-shin Street, Kwei-Shan, Tao-yuan 333, Taiwan.
Objectives: On completion of this article, the reader should be able to (1) understand gait parameter changes in the elderly population and in individuals with knee osteoarthritis, (2) interpret a sagittal ground reaction force diagram, and (3) understand the changes in the distribution of loading forces on the hindfoot, midfoot, and forefoot during walking in the elderly population and in individuals with knee osteoarthritis.
Accreditation: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to sponsor continuing medical education for physicians.
The Association of Academic Physiatrists designates this continuing medical education activity for a maximum of 1.5 credit hours in Category 1 of Physician’s Recognition Award of the American Medical Association. Each physician should claim only those hours of credit that he or she actually spent in the education activity.
Disclosure: Disclosure statements have been obtained regarding the authors’ relationships with financial supporters of this activity. There is no apparent conflict of interests related to the context of participation of the authors of this article.
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